Plus: more people from fan-favorite graphic novels and TV shows are coming to the Seaport this August.

A Dothraki warlord and other fictional creatures you are emotionally attached to are coming to the Seaport this summer. Jason Momoa (a.k.a. Khal Drogo from Game of Thrones) is among the many VIPs who will be in attendance at the 2014 Boston Comic Con, and the convention even added a third day to its lineup to fit them all—the event now takes place August 8 through 10.

In addition, fans will get close to other stars including James Marsters of Buffy the Vampire Slayer, John Barrowman of Doctor Who, Katie Cassidy from The CW’s Arrow, and Sean Astin of Lord of the Rings.

All the more reason for Momoa’s attendance at the convention, Variety just reported that the GoT actor will play Aquaman in the highly-anticipated Batman vs. Superman: Dawn of Justice movie starring Ben Affleck and Henry Cavill (sorry, it’s a no-go for Matt Damon). Other confirmed cast members in the overly scrutinized film are Jesse Eisenberg as Lex Luthor, Jeremy Irons as Alfred, and Amy Adams, Laurence Fishburne, and Diane Lane reprising their Man of Steel roles.

Marsters, who just ended his four-day stint in The Hound of the Baskervilles at UCLA, recently told the Hollywood Reporter that he’d absolutely consider reprising his role as Spike in Buffy—as long as they can find a way to have the vampire character not age. “What I don’t want to do is have an aging Spike apologetically telling Buffy that he’s under some aging spell,” he told the publication.

As for the other special guests at Comic Con, John Barrowman was recently honored by the Queen of England in her Birthday Honours List with a Member of the Order of the British Empire award. Katie Cassidy, who used to star alongside Jared Padalecki in Supernatural, was just at the Supanova pop culture expo a few days ago to represent Arrow.

And Sean Astin? He’s liking the idea of a Goonies sequel. But what else is new?

Boston Comic Con will take place Friday, August 8, through Sunday, August 10, at the Seaport World Trade Center, 200 Seaport Blvd., Boston. Tickets for admission, celebrity photo ops, single events, and more are on sale now at eventbrite.com.